Why Haven’t We Found the Missing Link in the Fossil Record? Science Answers!

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War is peace. Freedom is slavery. Ignorance is strength. -George Orwell

If evolution is such an incontrovertible “theory,” then why haven’t we found the “missing link” yet? A compelling question – if not boldly ignorant. In fact, creationists ask this question all the time, falsely asserting that there is a lack of evidence to support evolution. This article is going to look at why we don’t have all the information we want on the fossil record, and what the whole question of a “missing link” really means.

The More We Know

Though we have been seeking answers about our ancestral heritage throughout the ages, it’s no surprise that such a vast number of the scientific breakthroughs that inform our current body of scientific knowledge occurred in the last several decades. Why? Because, among other things, the technology that exists today obviously did not exist before. And in some cases, the information we have now overrides what was previously thought – which is a common theme in science, because science changes with evidence.

For example, the Swedish naturalist, Carl Linnaeus, had devised a system of classifying animals that we have adopted to this day, but this is unfortunately misleading. It is probably used today simply because people have become so used to these classifications. From Cyril Aydon’s book “A Brief History of Mankind“:

When Linaeus came to classify the primates (lemurs, monkeys, humans, etc.), he placed human beings in the genus Homo (which means ‘human’), and gorillas and chimpanzees in the genus Gorilla and Pan respectively. But he placed gorillas, chimpanzees and humans in the same sub-order, Anthropoidae (Latin for ‘human-like’). In doing so, he went against the religious teachings of his time, which held that human beings were unique among the animal creation. According to the Christian faith, as derived from the Bible, humans had been created ‘in the image of God,’ ‘to have dominion over all the beasts of the earth’. In Linnaeus’s view, humans were not sufficiently different from the great apes to justify any greater separation in their biological description.

Had the science of genetics existed in Linnaeus’s day, he would not even have separated gorillas, apes and humans this far. Common chimps and pigmy chimps (bonobos) share 99.3 per cent of their genes. Both kinds of chimp share 98.4 per cent of their genes with humans. This 1.6 per cent difference between chimps and humans is only about half the difference between chimps and humans on the one hand and gorillas on the other. There can be little doubt that, if Linnaeus had been classifying the primates in the 1990s, rather than in the 1750s, common chimps, bonobos and humans would now all be included in the genus Homo.

Having said that; despite the fact that we now know about the genetic similarities between humans, gorillas, and apes, the classification probably did not change simply because we got so used to it. New evidence often changes widely believed and universally taught “facts” – such as the notion that Pluto is a planet – but sometimes it doesn’t. At least now we know that the classical classifications given to animals is somewhat flawed, which is always valuable to science.

But let’s stay focussed on the technology of today. How might we be able to investigate features of a fossil? I won’t list technical procedures or get too specific, but just keep in mind that depending on how you examine a fossil, you may end up contaminating or destroying it; so obviously people are somewhat averse to working with the fossils directly. So many researchers prefer to make a copy of a fossil so that they can analyze it faster, or analyze it without even touching it. Luckily, we have technology to help.

Archeo-Technology

For one thing, we can now extract DNA from fossils, which is an amazing feat. Another thing we can do is to input the shape of the fossils into computers and analyze them digitally. This is especially helpful when you have, for example, skulls that have multiple pieces that don’t connect, such as if the jawbones have been worn away or destroyed over the centuries. With the technology available today,  we can see such skull in a digital 3D copy.

Take that a step further, and you get 3D printers, which are making it possible to print out the exact copy of skulls for people to analyze without having to worry about any damage being done to the original. The New Scientist reports a recent example of how this was used to great effect:

[Sergio Azevedo’s] team at the National Museum of Brazil in Rio used a portable CT scanner to determine the orientation of the specimen in the ground, then they cut out a large section of rock to take back to the lab. There the encased fossil was probed using a more powerful scanner – and a 3D replica printed out in resin.

Furthermore, the discovery last year of the remains of Richard III in a car park in England made international news a few months ago, because of the image that was able to be created. The Daily Mail reports:

The image is based on a CT scan taken by experts at the University of Leicester, who discovered the king’s skeleton with the help of the Richard III Society during an archaeological dig last September.

In an extraordinary find which challenges conventional historical accounts, the skeleton of the last of England’s medieval kings was identified by DNA analysis after researchers traced his living descendants. [. . .] The king’s facial structure was produced using a scientific approach, based on anatomical assessment and interpretation, and a 3D replication process known as ‘stereolithography’.

This is the image that came out of the process, unveiled on February 5, just a few months ago, next to the skull from which it derived:

Richard III fossil and image

Images as stunning as these are quite incredible. Obviously this kind of thing could not have been done very long ago, yet the fact that we already know so much about our history is astounding. Even without the technology we have available to us now, we have made huge strides in understanding our heritage. So if you consider only years – or a few decades at most (depending on the device) – of having certain technology available to us… how fast were you expecting scientists to learn everything about their ancestry from seven billion years ago?

“Why haven’t scientists answered all of our questions” is therefore an unfair question. The amount we have learned even within a few decades is astounding. So what about the “missing link”?

The “Missing Link”

The word “missing link” comes up all the time in West when people (i.e., creationists) debate about the fossil record. An article published last year by i09 nicely describes the problems of the “missing link” misnomer in terms of bipedalism – walking upright instead of on all fours.

Our early human ancestors began to walk on two legs a couple of million years ago, abandoning their old life of swinging between tree branches and perching in the leafy forest canopies of Africa. Now, a new study suggests that this transition from the trees to the ground was a long one. It appears that our ancestor A. Afarensis — typified by the 3.2 million-year-old “Lucy” fossil skeleton — lived at least part of her life in the trees. But she also walked on two legs.

What this means is that the whole idea of a simple “missing link” between humans and our ape cousins is false. There was no one, single moment when humans leapt from the trees to find a new existence on land. It happened gradually, over millennia, with different individuals from different species testing out what it would mean to live far from the protection of sheltering forests. Instead of thinking of our transition to walking as a “missing link,” it would be more accurate to say the transition was a long chain, in which one kind of life shaded into the other very gradually. [. . .]

What this new discovery highlights is the degree to which evolutionary changes don’t always have an easy beginning and ending. We’d like to believe there was a simple missing link between ape-like humans and human-like humans — perhaps a single species that provides a nice bright line between us and chimps. But the more we learn, the more we realize there is no species like that. There are species who started the exploration process, taking those first treks across the treeless savannahs, and there are species who continued that process.

To truly grasp how evolution works, we need to let go of the myth that there were radical distinctions between early human species. Evolution is a messy process, and it will never stop being messy. Modern humans are continuing the exploration process that A. Afarensis launched millions of years ago — and in another million years, we may have evolved an entirely new way of getting around. If we have, it won’t be because one day everybody woke up with a brand-new bone structure. It will be because over thousands of years, and millions of false starts, we slowly and irregularly transformed into a kind of human distinct from the ones who lived before.

Science20 published a massive article last year that looked at some of the arguments creationists frequently make, explaining why they are misleading:

Transitional fossils do exist. Its just that they aren’t necessarily the precise ancestors of organisms that we see; rather, are members of a cloud of organisms treading along some of the same evolutionary ideas, being as they are closely related to one another. Out of this maelstrom of different lineages there may be just one thread that gives rise to another important lineage. The fossils in this cloud still give us a chance to test our hypotheses about how the trends may have occurred in the lineages we’re interested in. But they may not necessarily [be] a true link in the chain.

That’s the true art of paleontology, you see: using examples from the fossil record to infer trends and to test hypotheses about the nature of evolution. To assume that it is simply trying to make a sort of flip-book of evolution through time is incredibly ignorant. [. . .]

A particularly egregious taunt often flaunted by creationists is “Give me just one missing link fossil and I will believe you”. It’s particularly loathsome because as soon as you present said creationist with a perfectly decent transitional fossil, they demand a link between those three fossils. And now there are two gaps to be filled with more missing links. Like the distance between Achilles and the tortoise in Zeno’s paradox, this continues ad infintum.

The Guardian published this article in 2009, just after “a team of Canadian and American scientists found a missing link between modern seals and their land-dwelling ancestors.”

No matter what you hear from anti-evolution groups in the US and UK, lack of scientific evidence isn’t the problem. The discovery of Puijila darwini was just the latest in a spectacular series of fossil finds demonstrating how evolution produced the first land vertebrates, the first whales, and even the first humans. Our own genomes carry the story of evolution, written in DNA, the language of molecular genetics, and the narrative is unmistakable. No, scientific evidence isn’t really what bothers most people about evolution.

What bugs them is that evolution carries with it a message they just don’t want to hear. That message is that we not only live in a natural world, but we are part of it, we emerged from it. Or more accurately, we emerged with it.

To them, that means we are just animals. Our lives are an accident, and our existence is without purpose, meaning or value.

My concern for those who hold that view isn’t just that they are wrong on science, wrong about the nature of the evidence, and mistaken on a fundamental point of biology. It’s that they are missing something grand and beautiful and personally enriching.

Evolution isn’t just a take-it-or-leave-it story about where we came from. It’s an epic at the centre of life itself. It tells us we are part of nature in every respect. Far from robbing our lives of meaning, it instils an appreciation for the beautiful, enduring, and ultimately triumphant phenomenon of life. [. . .]

Acknowledging that “missing link” between ourselves and the rest of the living world doesn’t demean human life – it enhances it. We may be animals, but we are not just animals. We are the only ones who can truly appreciate, as Darwin put it, that there is “grandeur in this view of life,” and indeed there is.

The Bottom Line

There are a lot of things to be said for the fact that the “missing link” notion is misleading. But the tactic of the creationist is to move the goalposts after each goal by a scientist is scored. So even if we discover every single fossil in the ground, die-hard creationists will still probably argue that the evidence does not stack up. It’s not even a matter of understanding it, it’s a willful ignorance – a lack of even trying to understand it. After all, many creationists don’t even argue against evolution; they argue against what they’re too intellectually lazy to discover is a theory of evolution that no scientists has ever even asserted. For example, the laughable notion that monkeys gave birth to humans.

It’s not even attacking a straw-man… it’s more like attacking the pole on which a straw man is supposed to be placed. But then, if you don’t have the straw-man in the first place, can you really erect a pole on which to sling your arguments? I’m skeptical. In fact, I’ll believe it when I see the missing link between poles and straw-men. Or as one American intellectual puts it:

If you don’t believe in God, then really you’ve got to have an explanation for this, and you just can’t tell me this spun out of a gastreous ball [. . .] then all of a sudden, then we were evolved from monkeys—why we still got monkeys? –Steve Harvey

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One Response to Why Haven’t We Found the Missing Link in the Fossil Record? Science Answers!

  1. Fanat says:

    You want people to guess what some ukonnwn animal might have eaten and crapped out millions of years ago? I mean it could be anything plant material, other animals, dirt? If you can interest a paleontologist, show it to them. Or take some good quality pictures and post it on a discussion board somewhere. But you have given us no information other than a lake in Texas, and when that fossil was made, most likely, neither the lake nor Texas were there.

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